The global orientation of today's machine manufacturers with clients/machine users located worldwide demands to be able to perform maintenance, fault detection and also repairs of the machine not only directly on site, but increasingly via remote access. In that application, under the term “machines” all machine facilities are summarized, e.g., for machining via laser, for punching or bending, and devices as, e.g., laser beam sources, plasma generators or induction generators. Dial-in directly from a service computer via an analogue modem or an ISDN-connection to a machine as it was common in the past will be replaced by recent communication technologies, especially by the so called Virtual Private Network (abbreviated VPN) allowing an encrypted remote access via the Internet. A remote access via VPN puts high requirements on the infrastructure and safety. The fact that the remote access via VPN is dependent on the technology applied by the machine operator is particularly problematic. A simple universal solution on the side of the machine manufacturer is thereby hindered that it is hitherto not possible to apply different VPN-software simultaneously within one operating system, e.g., on a service computer.
A system and a method for remote communication between a central computer and a machine controller are known from the European patent application EP 1 715 395 A1. The known remote communication system 1 shown in FIG. 1 comprises a central computer 5 which is protected by a firewall 6 to the outside. Several virtual machines 7 are installed on the central computer 5 which are executable simultaneously and can have different operating systems and application programs especially telepresence programs and antivirus programs. For each machine controller 3 there is a specific configured virtual machine 7 over which a communication link 8 will be established from the central computer 5 to the machine controller 3. The service computer 2 is not directly connected to the machine controller 3, but the connection of the service computer 2 is effected via the central computer 5 which is connected with the service computer 2 via a communication link 9. In a database 10 connected with the central computer 5 all data (dial-in technology, passwords, VPN-software) about the client and the machine 4 is stored. The central computer 5 determines the assigned communication link 8 on the basis of the data stored in the database 10 and the assigned virtual machine 7 and establishes the communication link 8 from the virtual machine 7 to the machine controller 3. The communication link 9 between the service computer 2 and the central computer 5 as well as the communication link 8 between the central computer 5 and the machine controller 3 are effected via the Internet 11, e.g., via a protected VPN-connection.
For remote access to a machine controller 3 of the machine 4 a service person at first prepares the communication link 9 between his service computer 2 and the central computer 5. On the basis of the data stored in the database 10, the central computer 5 determines the communication link 8 which is assigned to the machine controller 3 and selects the executable virtual machine 7 which is adapted to the machine controller 3 and the communication link 8 for the connection with the machine controller 3 and starts that virtual machine 7. The service person performs functions of the machine controller 3 via the communication link 8 or exchanges data between the machine controller 3 and the central computer 5.
A further advancement of the system and the method for remote communication from EP 1 715 395 A1 is known from DE 10 2008 030 317 A1. There it is disclosed that the executable virtual machine 7 is not permanently stored in the central computer 5, but virtual machine templates designed for different kinds of machine controllers and communication links. If required an executable virtual machine 7 is started and used as an executable embedded copy of that virtual machine template which is adapted to the respective machine controller and the respective communication link. After termination of the executable virtual machine 7 the executable embedded copy can be deleted.
It is a consequence of that system, that by the fact that the required maintenance software has to be provided in each virtual machine or machine template separately, here it comes to redundant application and data management. That leads to the result that for the virtual machine template, on the one hand large amounts of data have to be stored on the central computer, and on the other hand, because of the complexity of the virtual machine template, long starting times of the executable virtual machine 7 are to be expected. Further, for each of the virtual machine templates including a certain software required for maintenance, corresponding software updates have to be executed often to keep the environment up to date. That, in turn, leads to high maintenance effort.